Pink threw her 5-year-old little girl her very own party for becoming a big sister to the pop singer and Carey Hart's newborn son, James Moon Hart. In an absolutely precious photo shared to Instagram on Saturday, Willow beams from ear to ear while holding a chocolate cake that reads, "Congrats Big Sis!"

The proud mom of two holds her newest bundle of joy close by for the photo opp, captioning the moment, "Congrats Big Sis! #bigsisterparty"

The bash appears to have taken place at a local park, which the sweet trio decorated with light pink and blue balloons.

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Pink and Carey welcomed their second child together on the day after Christmas, taking to social media two days later to share the exciting news with her fans.

Since becoming a family of four, Willow has seemingly fit right into her role as Jameson's big sister and over New Year's Eve, was spotted cuddling the little guy. Too stinkin' cute!

Pink kept much of her second pregnancy under wraps, keeping the exciting news a secret until mid-November. The hot mama announced she was expecting on Instagram by posting an artistic photo of her little girl embracing an undeniable baby bump.